The invention relates to a light emitting module that may be, without limitation, used as a light source of a light irradiating apparatus configured to irradiate an irradiated object with light while a positional relationship between a light source section and the irradiated object is relatively varied in one direction.
In recent years, a development of a light source unit is in progress in which a plurality of light emitting elements are arrayed on the same plane. The light source unit may be linear or planar in shape, and the light emitting elements each may be a light emitting diode (LED) element, for example. The light source unit is used for an apparatus such as, but not limited to, a light treatment apparatus, an inspection apparatus, and a medical apparatus.
For such a light source unit, further increase in a packaging density of light emitting elements per unit area, improvement in extraction efficiency of light derived from each light emitting element, etc. have been desired in order to achieve light having higher power.
In general, a structure has been employed, as a technique to improve the extraction efficiency of light derived from the light emitting elements, in which the light emitting elements disposed on one surface of a substrate are, for example, sealed by a transmissive resin layer having a lens function. For example, reference is made to Japanese Unexamined Patent Application Publication No. 2008-108861 and Japanese Patent No. 5359732.
Referring to FIG. 10, for example, Japanese Unexamined Patent Application Publication No. 2008-108861 discloses a light emitting module 40a having a structure in which a light emitting element 45 as an LED chip, mounted on one surface 42 of a substrate 41 having a power supply wiring line, is sealed by a sealant 48 made of a transmissive resin having a lens function.
Referring to FIG. 11, Japanese Patent No. 5359732 discloses a light emitting module 40b in which a plurality of light emitting elements 45 are mounted on one surface 42 of a substrate 41. The disclosed light emitting module 40b has a structure in which the light emitting elements 45 are arrayed one dimensionally and lens sections 51 corresponding to the respective light emitting elements 45 are formed integrally with each other, and in which a lens array 50 made of a transmissive resin is so provided as to cover each of the light emitting elements 45.